My first critique. (Hope I will do well) This is one of your greates pixel works I have seen in your gallery~ It looks perfect: The colors match well and you have choosen the perfect contrast (not too strong but also not too weak). The animation is (nearly) completely smooth. I have also done some animations and I know how hard it can to make it 100% fluent. You have mastered the proportions of a chibi perfectly: The head does not seem too big which is the common mistake of chibis. I only rated the orginality one star lower because this is not a total original pose but it is one of the best I have seen in that way. In my opinion it reflects your stlye very well and you can see how much effort you have put in this cute pixel work. So, if you excuse me, I am going to die from cuteness now.
I'd be careful about marketing this as pixel art. Your color count is absurdly high. I think if we had a process of actually placing pixels individually, we can have smoother results and for example, have rounder irises. It may seem difficult to get them perfect if you're confined to a grid, but if you're familiar at all with antialiasing, we can easily have rounder irises if needed by defying the very grid we work with. It's kind of silly, to me as a pixel artist, to see aliased lines and smooth gradients in the same work, doesn't anything think?
I am not familiar with the subject at all, but what I find really interesting are the eye colors. Unlike other characters with two different eyes being two different colors, neither eye is colored to strongly attract more attention than the other. This completely avoids this annoying effect that I feel when looking at eye colors done this way.
You also took some effort animating your work, but if you ask me, the animation looks pretty fake.
If you take into account of Newton's third law of motion, unless that tail is literally weightless, the hips should very, very slightly shift to our right as it wags. It's also a bit funny to notice the light source on the tail change as it seems that you simple flipped the tail vertically, and I can tell that you created gradients on the tail, then rotated it for the purpose of creating more frames. You wind up messing with the quality of your shading as computers are kinda bad at rotating raster images.
We can also smooth out the animation by adding motion blur to the tail. The animation as of now looks a bit choppy.
The ears also move around, but somehow not displacing any of the hairs. There will be a lot more life to the hair if they also moved around very slightly as the ears displace them.
The irises also change shape (or at least moves around) as it blinks. Eyes don't do that, frankly. Eyes are very good at constantly being focused at certain directions.
Overall, a great piece, but the animation could use a bit of work. The 'cheating' tools used also makes it more difficult to control the quality of your animations too as you have less control of every pixel.